The present invention relates to an aiming apparatus for making transverse bores in bones in register with holes or bores of an osteosynthesis aid therein, especially an interlocking nail, comprising a holder for the accommodation of an aiming member adapted to be brought into the beam path of an X-ray apparatus.
Interlocking nails for the treatment of bone fractures, for instance, of the femur or the tibia, are fixed in the bone with the aid of transverse screws. In order that the transverse screws may be passed through the transverse bones in the interlocking nail, registered transverse bores must be made in the bone. It is that purpose the aiming apparatus serves.
An aiming apparatus has already become known comprising a an aiming head having a bore for the accommodation of an aiming sleeve and arranged at an elongated aiming head holding means in such a manner that it is adjustable longitudinally of the holding means (German utility model No. 78 05 301). The aiming head holding means is mounted in a fitting conntected to a source of x-ray radiation. The holding means is displaceably mounted in the fitting. The known aiming apparatus is connected to the x-ray apparatus and is dependent thereon. It has, therefore, also become known to provide a distal aiming apparatus which may be used independently of the type or make of the x-ray apparatus being used (German utility model) 82 08 970.1). With the known aiming apparatus a nail holding means is provided for the detachable accommodation of the proximal end of the interlocking nail approximately in parallel with the elongated aiming head holding means which in its turn is fitted at a holding arm displaceable about the axis of the interlocking nail in the nail holding means. The arm is detachably fitted at the aiming head holding means and is displaceable in a direction approximately in parallel with the nail axis in the aiming head holding means. Two adjusting pins may be received in the aiming head holding means vertically with respect to the axis of the interlocking nail. The known apparatus is distinguished for its relatively high grade aiming accuracy, indeed, but the handling thereof is very much time consuming. Besides, expenditure in terms of costs relating to the apparatus proper is considerable.
The invention is based upon the problem of providing a distal aiming apparatus which is distinguished for a simple and quick handling thereof in spite of a high grade aiming accuracy.